You are getting good advice here. The 911 calls were recorded. Your mom witnessed the shoving. Self-defense is perfectly acceptable, but it's harder to prove when the abuser makes the initial report.
Hopefully the police/prosecutor/judge are all well-trained in DV. This sort of thing happens ALL the time. There is actually a rule in NJ that requires the police to sort out who was the initial aggressor when both parties have injuries.
Please deal with this now, full force. His being arrested in front of the girls is nothing compared to the damage they will suffer if he continues to abuse you (whether in front of them or not). You were threatened and assaulted. Those are crimes. He has no one to blame but himself, though he certainly will try to blame you. Don't back down. Get help, call a DV counselor who can help you plan for your safety.